Response Insights offers data-backed suggestions to improve the predicted reply rates of your messages. You can learn all about the algorithm here. Please note, this BETA feature is only available on Gmail.
You can remove the Insights widget from the compose window by turning it off in your preferences.
To do so, go to the Yesware menu at the top left of your Gmail inbox and select "Preferences." Navigate to the “Inbox” section, scroll down to the “Response Insights -- Composer Widget,” and toggle it to the "Off" position.
Please note, removing the widget from your compose window will not remove the Response Insights tab from your Yesware Sidebar. You will still be able to manually click the tab to view your email grade.